1. Field of the Invention
The present invention relates to a resin molded component whose surface is coated with metal by physical deposition method for practical use.
2. Description of the Related Art
Printed circuit boards such as MID, sensor parts, reflectors and the like are manufactured by fabricating a resin molded component by injection-molding a resin composition, and by coating the surface of the resin molded component with a metal layer serving as circuits and reflecting films by physical deposition method such as sputtering, vacuum evaporation, and ion plating.
The resin composition that forms the resin molded component comprises of a thermosetting resin or a thermoplastic resin, and the resin molded component generally provides a low adhesion to metal. In particular, when the metal layer is formed on the surface of the resin molded component by the physical deposition method which is a dry method such as sputtering, vacuum evaporation, and ion plating, it is still more difficult to obtain the adhesion between the resin molded component and the metal than by wet method such as electrolysis or electroless plating.
Therefore, in order to improve the adhesion of the metal layer to the resin molded component, the surface of the resin molded component is plasma-treated. This plasma treatment is carried out in the activated gas atmosphere such as oxygen, nitrogen and the like, wherein ions of such as oxygen, nitrogen and the like in the plasma act on the surface of the resin molded component to activate it by providing particles on the surface of the resin molded component with a polar group such as oxygen polar group, nitrogen polar group and the like, resulting in improving the adhesion of the metal layer to the resin molded component.
However, in the present situation it is still difficult to obtain a high effect of improving the adhesion between the resin molded component surface and the metal layer only by activating the surface by plasma treatment.